Ever heard of phthalates? They're a class of chemicals used to soften plastics found in everything from household containers to medical supplies, and to stabilize colors and fragrances in cosmetics like lipstick and perfume.

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The most widely known phthalate is probably bisphenol-A (BPA), which has been linked to breast cancer and a whole mess of complications with hormone regulation.* One of the most widely used phthalates is Di-2-ethylhexyl phthalate (DEHP). DEHP is a plasticizer commonly used in IV bags and tubing, and newly published research shows that exposure to DEHP is linked to high blood glucose levels and insulin resistance — two precursors of type II diabetes. The study also reveals that high rates of exposure to phthalates may as much as double the rate of diabetes in black and Mexican American women.

In the new research, certain phthalates – dibutyl phthalates (DBP), which are primarily used in adhesives and lacquer finishes, and benzyl butyl phthalate (BBP), a component of vinyl flooring, caulks and sealants – were linked to double the rate of diabetes in women with the highest levels of phthalate markers in their urine, according to the report published this month in Environmental Health Perspectives.

DBP and Di-2-ethylhexyl phthalate (DEHP), a plasticizer found in vinyl products including IV bags and tubing, were also linked to higher blood glucose levels and insulin resistance, two common precursors of type 2 diabetes, according to the study.

Industry groups are obviously pushing back on these findings, and hard. Steve Risotto, senior director fo the American Chemistry Council, a trade association for chemical manufacturers, described the researchers' experimental methods as "flawed," and while study co-author Richard Stahlhut cedes that her team's results are preliminary, she and her colleagues are confident in their results:

These findings are important clues, but it's only a first step... It's extremely likely that phthalates and other chemical contaminants will turn out to be a big part of the obesity and diabetes epidemic, but at this point we really don't know how these chemicals are interacting with each other, or with the human body. [emphasis added]

*Correction: While it is commonly used in the production of plastics, and its adverse health effects have been well documented, bisphenol-A is NOT a phthalate. As @chemjobber rightfully pointed out on twitter, the phthalate esters used in plastics are derivatives of phthalic acid. BPA is not a derivative of phthalic acid. It's not even an ester. Needless to say, it's not a phthalate.